This invention relates to vapor compression distillers.
Vapor compression distillers generally include a heat exchange tube bundle and a feed liquid distributor for delivering feed liquid over the outer surfaces of the heat exchange tubes. A vapor is simultaneously delivered to the interior of the tubes and condenses as it gives up its heat of vaporization to the feed liquid. This causes a first portion of the feed liquid to evaporate and a second portion to collect in the lower end of the apparatus. The vaporized feed liquid is compressed and recirculated back to the inlet of the heat exchange tubes while fresh feed liquid is delivered to the system to compensate for evaporated liquid and concentrate which may be withdrawn.
Certain feed liquids such as kraft paper waste sulfate liquor, there is a tendency for the feed liquid to foam as it is distributed downwardly over the heat exchange tubes. System efficiency is substantially diminished if the foam is drawn into the compressor.